The present invention relates to a spray gun assembly structure wherein a connecting tube has a second coupling head with two waterproof rings mounted thereto to abut tight against the internal surface of a conjoining tube of a spray gun and form a dual water-sealing benefit, and a stop flange disposed beneath the coupling head is enclosed between the conjoining tube and a locking tube, permitting the spray gun to achieve accurate water shutoff state no matter under high or lower water pressure. Besides, depending on the extension and twist of the spray gun, the coupling shaft and the stop flange of the second coupling head can be rotated and automatically adjusted in position, facilitating stable handling and easier operation of the spray gun thereby.
A conventional spray gun mounted to the kitchen or bathroom for cleaning is integrally assembled to a connecting tube into one unit. And, depending on the locations of cleaning, the spray gun must be constantly moved and turned in application. When the connecting tube is stretched, it will also be twisted along with the spray gun. As a result, the connecting tube can easily get tied and wound up, which can badly influence the water discharge and make difficult handling of the spray gun. Then, the connecting tube must be readjusted in position over and over again, which, in the long run, can easily damage the connecting tube and reduce its durability thereby. Thus, it not only wastes the resources and money, but also increases the burden of the environment. In addition, the conventional spray gun with the connecting tube simply includes a T-shaped head fixed with screw nuts in one-way force, which usually causes the problem of water leakage. It's not only that the spray gun cannot shut off the water discharge via internal and external ways thereof, the connecting tube also can not accurately seal off the water discharge. Thus, the problems of water leakage and the return of remaining water can happen again and again, which can ruin the hygiene of the bathroom or kitchen as well as cause a waste of water resource.